What has been fixed in Calibre 9.7 AI functions?

Improved GitHub backend reliability; fix for OpenRouter error where 'auto' disabled logical inferences.

What new features in the viewer?

Annotations browser with grouping by fields; 'pinch' gesture on touchpad for font change.

Does Calibre 9.7 support Linux devices?

Yes, MTP driver fix eliminates crashes when connecting devices with large collections.

Calibre 9.7: AI and content server fixes

Calibre 9.7 focuses on fixing bugs in the viewer, AI, and content server. Added annotation grouping, touchpad gesture support, and autonomous HTTPS mode. Update improves stability for cross-platform libraries.

By Sudonull Editorial Team • Published 2026-04-14 • Updated 2026-04-14

Calibre 9.7: Bug Fixes in Viewer, AI, and Content Server

On April 10, 2026, version 9.7 of the open-source Calibre project was released—a cross-platform e-book manager. Built on Python and C under the GNU GPL v3.0 license, it supports Windows, macOS, and Linux. Since the 7.0 release in November 2023, the project has evolved: 8.0 in March 2025, 9.0 in January 2026. Calibre handles viewing, conversion, editing, and cataloging of books in major formats, syncs with e-ink devices, extracts metadata, and converts newspapers.

In version 8.11, an "Ask AI" tab was added to the viewer: queries to selected text via providers like Google, OpenRouter, GitHub, or local Ollama models. The feature is optional—AI code loads only after setup.

Bug Fix Details

Version 9.7 addresses non-critical bugs accumulated in previous releases. Key fixes:

Viewer: annotations and last reading data now save correctly in EPUB and other formats.
GitHub AI backend: improved reliability of requests and response handling.
OpenRouter and AI: "auto" mode for logical inference no longer disables all outputs.
Content server: fixed crash during search in reading mode; full-text search returns results without issues.
Full-text search: refined the new interface layout.
MTP driver on Linux: fixed rare crashes when connecting devices with large libraries (>10k books).
Adding files: covers now set for entries without them.

These changes boost stability for mid/senior developers using Calibre in library automation pipelines or e-book API integrations.

New Features

The update introduces features for easier work with annotations and devices:

Annotations browser: grouping by any field (author, tag, date) with sorting and filters.
Viewer: pinch gesture support on trackpad for scaling—by default changes font size, like on touchscreen.
Content server: full offline mode for HTTPS connections, no dependency on external resources.

Additionally, added news source Cenital by Rodrigo Pazos; improved The Week, The Age, Financial Times, Mint—faster RSS loading and metadata parsing.

Key Points

AI Stability: GitHub and OpenRouter fixes ensure predictable queries to selected text without false disables.
Content Server: Autonomous HTTPS mode simplifies deployment in isolated networks.
Annotations: Grouping speeds up analysis of large collections for automated workflows.
Cross-Platform: Linux MTP fix resolves issues with Android devices in enterprise environments.
News Updates: New/improved sources for daily content monitoring.

The project has been developing for 11+ years, focusing on robustness without unnecessary dependencies. For developers: source code on GitHub allows forking and patching for custom needs, e.g., integration with local LLMs via Ollama API.

— Editorial Team